[Federal Register Volume 64, Number 16 (Tuesday, January 26, 1999)]
[Rules and Regulations]
[Pages 3823-3825]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-1430]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-SW-21-AD; Amendment 39-11011; AD 98-11-14]
RIN 2120-AA64
Airworthiness Directives; Bell Helicopter Textron, Inc. Model
205A-1 and 205B Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This document publishes in the Federal Register an amendment
adopting Airworthiness Directive (AD) 98-11-14 which was sent
previously to all known U.S. owners and operators of Bell Helicopter
Textron, Inc. (BHTI) Model 205A-1 and 205B helicopters by individual
letters. This AD requires inspecting the trunnion assembly or tail
rotor flapping stop (flapping stop), whichever is applicable,
installing a trunnion assembly or flapping stop, if necessary; and
replacing the tail rotor yoke (yoke). This amendment is prompted by an
accident involving a BHTI Model 205A-1 helicopter in which the yoke
failed during flight. This condition, if not corrected, could lead to
failure of the yoke, loss of the tail rotor, and subsequent loss of
control of the helicopter.
DATES: Effective February 10, 1999, to all persons except those persons
to whom it was made immediately effective by Priority Letter AD 98-11-
14, issued on May 19, 1998, which contained the requirements of this
amendment.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 10, 1999.
Comments for inclusion in the Rules Docket must be received on or
before March 29, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Office of the Regional Counsel, Southwest Region,
Attention: Rules Docket No. 98-SW-21-AD, 2601 Meacham Blvd., Room 663,
Fort Worth, Texas 76137.
The applicable service information may be obtained from Bell
Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101,
telephone (817) 280-3391, fax (817) 280-6466. This information may be
examined at the FAA, Office of the Regional Counsel, Southwest
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Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the
Office of the Federal Register, 800 North Capitol Street, NW., suite
700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Harry Edmiston, Aerospace Engineer,
FAA, Rotorcraft Certification Office, Rotorcraft Directorate, 2601
Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5158, fax
(817) 222-5783.
SUPPLEMENTARY INFORMATION: On May 19, 1998, the FAA issued Priority
Letter AD 98-11-14, applicable to BHTI Model 205A-1 and 205B
helicopters, which requires, before further flight, reviewing
historical records of the helicopter and yoke assembly to detect any
usage or event that may have imposed an excessive bending load on the
yoke. If such usage or event occurred, before further flight, the
priority letter AD requires replacing the yoke assembly with an
airworthy yoke assembly that has zero-hours time-in-service (TIS) or
that has passed an x-ray diffraction inspection in accordance with
BHTI's service bulletins, as well as installing an airworthy trunnion
assembly or an airworthy flapping stop, depending on which part-
numbered yoke assembly is installed. If no such usage or event has
occurred, the yoke must be replaced within 180 calendar days.
Thereafter, at intervals not to exceed 25 hours TIS, or before further
flight after any incident that may have imposed an excessive bending
load on the yoke, this AD requires inspecting the trunnion assembly or
the flapping stop, whichever is applicable, for yielding. If yielding
is detected, replacing the yoke assembly and trunnion assembly or
flapping stop, whichever is applicable, is required. That action was
prompted by an accident involving a BHTI Model 205A-1 helicopter in
which the yoke failed during flight. Investigation of the accident
revealed that the yoke assembly service life may be reduced due to
unforeseen static and dynamic loading of the tail rotor. This
condition, if not corrected, could lead to failure of the yoke, loss of
the tail rotor, and subsequent loss of control of the helicopter.
The FAA has reviewed Bell Helicopter Textron, Inc. Alert Service
Bulletin (ASB) No. 205-96-68, Revision A, dated May 18, 1998, which
specifies inspecting the yoke and trunnion assemblies, and replacing
certain trunnion assemblies; and ASB 205-96-69 and ASB 205B-96-25, both
dated September 3, 1996, which specify inspecting the yoke assembly and
installing a flapping stop.
Since the unsafe condition described is likely to exist or develop
on other BHTI Model 205A-1 and 205B helicopters of the same type
design, the FAA issued Priority Letter AD 98-11-14 to prevent failure
of the yoke, loss of the tail rotor, and subsequent loss of control of
the helicopter. The AD requires, before further flight, reviewing
historical records of the helicopter and yoke assembly to detect any
usage or event that may have imposed an excessive bending load on the
yoke. If such usage or event occurred, this AD requires, before further
flight, replacing the yoke assembly with an airworthy yoke assembly
that has zero-hours TIS, or that has passed an x-ray diffraction
inspection in accordance with Bell Helicopter Textron, Inc. Alert
Service Bulletin (ASB) 205-96-68, Revision A, dated May 18, 1998, or
ASB 205-96-69 or ASB 205B-96-25, both dated September 3, 1996,
whichever is applicable, as well as installing an airworthy trunnion
assembly or an airworthy flapping stop, depending on which part-
numbered yoke assembly is installed. If no such usage or event has
occurred, the yoke must be replaced within 180 calendar days.
Thereafter, at intervals not to exceed 25 hours TIS, or before further
flight after any incident that may have imposed an excessive bending
load on the yoke, this AD requires inspecting the trunnion assembly or
the flapping stop, whichever is applicable, for yielding. If yielding
is detected, replacing the yoke assembly and trunnion assembly or
flapping stop, whichever is applicable, is required. The actions are
required to be accomplished in accordance with the service bulletins
described previously. The short compliance time involved is required
because the previously described critical unsafe condition can
adversely affect both the controllability and structural integrity of
the helicopter. Therefore, the previously-stated actions are required
prior to further flight, and this AD must be issued immediately.
Since it was found that immediate corrective action was required,
notice and opportunity for prior public comment thereon were
impracticable and contrary to the public interest, and good cause
existed to make the AD effective immediately by individual letters
issued on May 19, 1998 to all known U.S. owners and operators of BHTI
Model 205A-1 and 205B helicopters. These conditions still exist, and
the AD is hereby published in the Federal Register as an amendment to
section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to
make it effective to all persons.
The FAA estimates that 495 helicopters of U.S. registry will be
affected by this AD; that it will take approximately 9 work hours per
helicopter to conduct the inspections, install the trunnion assembly or
flapping stops, and replace the yoke; and that the average labor rate
is $60 per work hour. Required parts will cost approximately $1,028 for
a trunnion assembly or $936 for the flapping stops and $6,637 for the
yoke, per helicopter. Based on these figures, the total cost impact of
the AD on U.S. operators is estimated to be $4,061,475 to replace both
the trunnion assembly and the yoke in the entire fleet.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications should identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the rule. All comments submitted will be
available, both before and after the closing date for comments, in the
Rules Docket for examination by interested persons. A report that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket No. 98-SW-21-AD.'' The postcard will be date stamped and
returned to the commenter.
The regulations adopted herein will not have substantial direct
effects on the States, on the relationship between the
[[Page 3825]]
national government and the States, or on the distribution of power and
responsibilities among the various levels of government. Therefore, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, may be obtained from the Rules Docket at the
location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive
to read as follows:
98-11-14 Bell Helicopter Textron, Inc.: Amendment 39-11011. Docket
No. 98-SW-21-AD.
Applicability: Model 205A-1 helicopters, with tail rotor yoke
assembly, part number (P/N) 212-011-702-all dash numbers, or P/N
212-010-704-all dash numbers, or P/N 212-010-744-all dash numbers,
and Model 205B helicopters, with tail rotor yoke assembly, P/N 212-
011-702-all dash numbers, installed, certificated in any category.
Note 1: This AD applies to each helicopter identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For helicopters that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (d) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition, or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any helicopter from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent failure of the tail rotor yoke (yoke), loss of the
tail rotor, and subsequent loss of control of the helicopter,
accomplish the following:
(a) Before further flight, review all historical records of the
helicopter and the tail rotor yoke assembly (yoke assembly) for any
static or dynamic incident history that could have imposed an
excessive bending load on the yoke. If such a history exists, comply
with paragraph (b) of this AD before further flight.
Note 2: Examples of excessive bending loads include exposure to
high wind gusts (such as those from rotor wash or prop blast),
improper ground handling (in which the tail rotor blade has been
used as a hand hold), improper feathering bearing removal (in which
the yoke is not properly supported when pressing out bearings), a
static ground strike of some type (such as being struck by a
vehicle), or an incident in which a damaged tail rotor blade was
replaced due to a blade strike. An overload may also occur
dynamically during a power-on or power-off sudden stoppage incident
or hard landing.
(b) Within the next 180 calendar days, remove the yoke assembly
and replace it with an airworthy yoke assembly having zero hours
time-in-service (TIS), or with an airworthy yoke assembly
(regardless of TIS) that has passed an x-ray diffraction inspection
in accordance with Bell Helicopter Textron, Inc. Alert Service
Bulletin (ASB) 205-96-68, Revision A, dated May 18, 1998, or ASB
205-96-69 or ASB 205B-96-25, both dated September 3, 1996, whichever
is applicable. When the yoke assembly is replaced, for helicopters
with a yoke assembly, P/N 212-011-702-all dash numbers, install an
airworthy tail rotor flapping stop, P/N 212-011-713-103, and for
helicopters with yoke assemblies, P/N 212-010-704-all dash numbers
or P/N 212-010-744-all dash numbers, install an airworthy trunnion
assembly, P/N 212-010-738-001. If any incident as described in
paragraph (a) of this AD occurs after the effective date of this AD
and prior to compliance with this paragraph, then compliance with
this paragraph is required before further flight.
Note 3: Yoke assemblies that have passed an x-ray diffraction
inspection at BHTI will have the letters ``FM'' vibro-etched on them
following the serial number.
(c) After accomplishing the requirements of paragraph (b) of
this AD, thereafter at intervals not to exceed 25 hours TIS, or
before further flight after any incident as described in paragraph
(a) of this AD, inspect the trunnion assembly, and replace the yoke
assembly and trunnion assembly, if required, in accordance with Part
III, Paragraph 1, of ASB 205-96-68, Revision A, dated May 18, 1998;
or inspect the flapping stop and replace the yoke assembly and
flapping stop, if required, in accordance with Part III, Paragraphs
1, 2, and 3, of ASB 205-96-69 or ASB 205B-96-25, both dated
September 3, 1996, whichever is applicable.
(d) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Rotorcraft Certification Office,
Rotorcraft Directorate. Operators shall submit their requests
through an FAA Principal Maintenance Inspector, who may concur or
comment and then send it to the Manager, Rotorcraft Certification
Office, Rotorcraft Directorate.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Rotorcraft Certification Office.
(e) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the helicopter to a location where
the requirements of this AD can be accomplished.
(f) The repetitive inspections shall be done in accordance with
Bell Helicopter Textron, Inc. Alert Service Bulletin (ASB) No. 205-
96-68, Revision A, dated May 18, 1998, which specifies inspections
of the yoke and trunnion assemblies, and replacement of certain
trunnion assemblies; and ASB 205-96-69 and ASB 205B-96-25, both
dated September 3, 1996, which specify inspections of the yoke
assembly and installation of a flapping stop. This incorporation by
reference was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be
obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort
Worth, Texas 76101, telephone (817) 280-3391, fax (817) 280-6466.
Copies may be inspected at the FAA, Office of the Regional Counsel,
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas;
or at the Office of the Federal Register, 800 North Capitol Street,
NW., suite 700, Washington, DC.
(g) This amendment becomes effective on February 10, 1999, to
all persons except those persons to whom it was made immediately
effective by Priority Letter AD 98-11-14, issued May 19, 1998, which
contained the requirements of this amendment.
Issued in Fort Worth, Texas, on January 14, 1999.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-1430 Filed 1-25-99; 8:45 am]
BILLING CODE 4910-13-P